A standard data center can be configured with rows of racks or cabinets that have installed therein a variety of assets or electronic systems, such as computing systems, networking systems, communications systems, or other types of electrical devices. The data center equipment rack assets (e.g., computers, storage devices, servers, routers, networking devices, communications systems, etc.) consume electrical power for their operation. The computing systems, networking systems, and communications systems of the data center may reside in these racks. In a typical data center, there may be dozens or even hundreds of electrical devices. Each of these devices is connected to an electrical power source. Each of these assets needs to be identified and managed in an efficient manner.
The problem of managing assets in a data center equipment rack is complex for several reasons. First, the quantity of devices that consume power can be very large. Any solution will need to be cost effective and will need to apply to large as well as small data centers or collections of electronic assets. Secondly, data centers use a variety of devices and mechanisms to deliver power. Any solution will need to address the heterogeneity and legacy issues in the data center. Finally, a large number of devices or systems in data centers can be idle or outdated.
In some cases, data center operators have responded by installing Smart power strips, power distribution strips, or rack Power Distribution Units (PDUs) that can deliver and measure power at the rack or at the plug level. Some of these PDUs can use the Internet Protocol (IP) network to transfer this information. Unfortunately, the networking capabilities of many of the conventional PDUs are not utilized because of the cost and complexity of connecting them to the IP network.
Electrical power in data centers is typically distributed from Uninterruptable Power Systems (UPS) to servers from Power Distribution Units (PDUs) that transform the voltage from 480 VAC to 208/110 VAC to internal electrical distribution panel boards or external power panel boards. The panel boards contain individual electrical circuits of various current or amperage capacities. These electrical power circuits are connected to power distribution strips containing electrical outlets in equipment racks placed in the data center to supply the power needs of electronic assets in the equipment racks.
The power distribution topology provided in the data center may be single path or non-redundant with only one set of UPS. PDUs can be installed to provide power to the servers with a single power supply and one plug connection. The topology may also be dual path or redundant whereby multiple UPS systems and two sets of PDUs are installed to provide power from two different electrical systems to each server, which is designed with redundant power supplies that are powered independently from two rack power distribution units or strips (PDUs). In another data center electrical topology, a primary UPS of a redundant set of UPS systems feeds single PDUs through static transfer switches (STS). If the primary UPS fails, the STS automatically switches the PDU to the alternate back-up source UPS of the redundant set of UPS systems.
Each server's maximum power requirement at full load is required to be provided to the outlet plug in either a single or dual path topology. To meet this requirement each power distribution strip is fed from a PDU electrical circuit that may vary in voltage and power capacity as required by the information technology (IT) equipment to be housed in each equipment rack.
The number and type of servers that may be housed in a specific equipment rack is bound by how much electrical load can be put on each circuit (known as circuit capacity), which typically is between 20-100 amps per circuit. Power is fed from the PDU through the power distribution panel and through a circuit breaker, which is a device that enables a safe means of turning off power being fed from the PDU to the rack power strips for installation and maintenance purposes and to protect the electrical power distribution system from overloading and damage if the server load connected to the circuit exceeds its rated maximum capacity. Given the complexities of the various aggregations of data center equipment, some mechanism is needed to enable data center operators to remotely manage data center equipment and the power consumption of data center equipment.